Last year, more than a third of Chevron Corp. shareholders voted to strip Chief Executive Officer John Watson of his other title - chairman of the oil company's board.

Now Chevron wants to keep the idea from coming back for another vote.

Chevron has asked federal regulators to let the company block a nearly identical proposal from discussion at this year's shareholders meeting. It's one of two shareholder proposals that the San Ramon company has asked the Securities and Exchange Commission for permission to block.

Both deal with a long-running, $19 billion pollution lawsuit against Chevron in Ecuador. The shareholders pushing the proposals want Chevron to settle the suit. Company executives call the suit extortion and have vowed never to pay.

Instead, Chevron has pushed back against its activist shareholders. Last fall, the company even subpoenaed documents from some of them. The second proposal Chevron seeks to block asks the company's board to explain the rationale behind those subpoenas.

"The feeling among institutional shareholders is we really have to draw a line in the sand here, because we can't have companies using these tactics against shareholders in the future," he said.

A Chevron spokesman said the company is trying to block a resolution that had appeared in slightly different forms at several past shareholder meetings and lost each time. The company's board noted as much last year, in a message urging shareholders to vote against the idea.

Similar proposals

The commission has not issued a decision. But Chevron spokesman Morgan Crinklaw said other companies, including Clorox and Procter & Gamble, have won the commission's permission to exclude similar proposals on similar grounds.

Chevron initially argued that the proposal for an independent board chairman was too vague, because it didn't define "independent." The Unitarians then suggested tweaking the language to include such a definition. Chevron countered that the changes would substantially alter the proposal, something the commission usually doesn't allow.

Many companies keep the jobs of CEO and board chairman separate as a way to hold top executives accountable for their performance. The idea won the support of 38 percent of Chevron shareholders last year - well short of a majority, but still a substantial show of support.

Billenness and the proposal's other backers don't just consider the idea a matter of good corporate governance. They say Watson is too personally vested in the Ecuador lawsuit and needs the oversight of an independent chairman.

The lawsuit was filed in 1993 against Texaco, which drilled for oil in Ecuador from 1964 through 1992. Residents of the area accused Texaco of contaminating the land and water, triggering a wave of disease.

Chevron bought Texaco in 2001, inheriting the suit. And Watson played a key role in that purchase. At the time, he served as Chevron's vice president of strategic planning, mergers and acquisitions. He became CEO at the end of 2009.

$19 billion fine

Ecuadoran courts have ruled against Chevron, fining the company $19 billion. Chevron calls the verdict the product of a criminal conspiracy and has filed a racketeering lawsuit in the United States against the Ecuadorans' lawyers. (The subpoenas against activist shareholders were part of that suit, as the company looked for links between the shareholders and the people Chevron accuses of judicial fraud.)

Meanwhile, the Ecuadorans have taken Chevron to court in other countries where the company has assets that can be seized to pay off the judgment. A court in Argentina last year froze $2 billion of Chevron's assets as a result.

"As we got deeper into this, it became clear that it's not just a question of Chevron being unwilling to clean up its pollution and deal fairly with the affected communities," Billenness said.

"There's also a question here for shareholders as to whether Chevron's management has actually jacked up the risk with this kind of scorched-earth legal strategy."